Effects of both Sympathetic and Parasympathetic divisions on
different organs.
Sympathetic receptors α1, α2
β 1,
β 2, β
3
parasympathetic
receptors M1,M2,M3
1- Cardio-vascular system
a- Heart
Target
site
|
Sympathetic
|
Parasympathetic
|
Cardiac output
|
(β1) increases
|
(M2) decreases
|
SA node: heart rate (Chronotropic )
|
(β1) increases
|
(M2) decreases
|
Contractility (Inotropic)
|
(β1) increases
|
(M2) decreases
|
AV node
|
(β1) increases condution
|
(M2) decreases conduction
|
b- Blood Vessels
Target site
|
Sympathetic
|
Parasympathetic
|
Skin,Brain,Kidney,Erectile
tissue,salivary glands, Viscera
|
(α1)constriction
|
Erectile tissues and salivary glands
only (M3) dilates
|
Hepatic , skeletal muscle, coronary
arteries
|
(β2)dilates
|
______________
|
c- Others :
Target site
|
Sympathetic
|
Parasympathetic
|
Platelets
|
(α2) aggregation
|
--------------
|
Mast cells (release of histamine)
|
(β2) inhibition
|
--------------
|
2- Respiratory system :
Target site
|
Sympathetic
|
Parasympathetic
|
Smooth muscles of bronchioles
|
(β2) relaxation of muscles
|
(M2) contraction
|
3- Eye
Target site
|
sympathetic
|
Parasympathetic
|
Iris radial muscle
|
(α1)pupil dilates( mydriasis )
|
------------
|
Iris sphincter muscle
|
--------------
|
(M3) pupil contracts (Miosis)
|
Ciliary muscle
|
(β2)relaxe long range focus
|
(M3)contract short range focus
|
4- GIT
Target site
|
Sympathetic
|
Parasympathetic
|
GIT
motility
|
decrease
|
M3, (M1) increases
|
GIT sphincters
|
(α1) contracts
|
M3 relaxation
|
GIT glands
|
---------------
|
(M3) increase secretions
|
5-
Urinary System
Target site
|
Sympathetic
|
Parasympathetic
|
Detrusor
|
(β2)
relaxation
|
(M3) contraction
|
Urethral sphincter
|
(α1)
contraction
|
(M3) Relaxation
|
Sympathetic cause retention while
parasympathetic cause evacuation
6-
Reproductive system
Target site
|
Sympathetic
|
Parasympathetic
|
Uterus (female)
|
(β2)
relaxation
|
-------------------
|
Genitalia (male)
|
(α1)
ejaculation
|
(M3) Erection
|
7-
Metabolism
Target site
|
Sympathetic
|
Parasympathetic
|
Liver
|
(β2)
glycogenolysis and gluconeogenesis
|
----------------
|
Kidney
|
(β1)
increase rennin release
|
------------
|
Pancreas
|
(β2)
increase insulin release(minor effect)
(α2)decrease
insulin release(major effect)
|
8-
Adipose tissue
(β1)
cause lipolysis
9-
Skin:
α1 cause stimulation of arrector pili
